Formation of polyethylene from calcium carbide takes place as follows :
$\begin{array}{l}{\mathrm{CaC}}_2+2{\mathrm{H}}_2\mathrm{O}⟶\mathrm{Ca}(\mathrm{OH}{)}_2+{\mathrm{C}}_2{\mathrm{H}}_2;\\ {\mathrm{C}}_2{\mathrm{H}}_2+{\mathrm{H}}_2⟶{\mathrm{C}}_2{\mathrm{H}}_4;\\ {\left.{\mathrm{nC}}_2{\mathrm{H}}_4⟶{(\mathrm{CH}}_2-{\mathrm{CH}}_2\right)}_{\mathrm{n}}\end{array}$
The amount of polyethylene obtained from 64. 0kg of CaC₂ is

 The molar mass of CaC₂​ is 64 g/mol.

 64 kg (or  64000 g) of CaC₂​= $\frac{64000 \mathrm{g}}{64 \mathrm{g}/\mathrm{mol}}$​= 1000 mol .

1000 moles of CaC₂​= 1000 moles of C₂​H₂​

1000 moles of C₂​H₂​= 1000 moles of C₂​H₄​

The molar mass of C₂​H₄​ is 28 g/mol.

1000 moles of C₂​H_4​= 1000 mol× 28 g/mol= 28000 g or 28 kg.

 28 kg of C_2​H_4​ will give 28 kg of polythene.